Light guide plate, display device having the same, and method thereof

Abstract

A light guide plate and a display device having the same are provided, which can uniformly emit light on the whole. The light guide plate includes a light input part including first and second areas to which light is incident, and a light output part neighboring the light input part and outputting light. The light having passed through the first area is emitted with its light quantity distribution biased in a first direction, and the light having passed through the second area is emitted with its light quantity distribution biased in a second direction different than the first direction.

1. A light guide plate comprising:
 a light input part including first and second areas to which light is incident; and 
 a light output part neighboring the light input part and outputting light; 
 wherein the light having passed through the first area is emitted with its light quantity distribution biased in a first direction, and the light having passed through the second area is emitted with its light quantity distribution biased in a second direction different from the first direction, and 
 wherein
 the first area includes a row of a first serration pattern each including a first serrated thread adjacent to a normal line of the light output part, 
 the second area includes a row of a second serration pattern each including a second serrated thread adjacent to the normal line, 
 the first serrated thread overlaps the second serrated thread, and 
 the second serrated thread is inclined from the normal line in a different direction than the first serrated thread. 
 
 
     
     
       2. The light guide plate of  claim 1 , wherein the first and the second serration patterns are symmetrical to each other around the normal line of the light input part. 
     
     
       3. The light guide plate of  claim 2 , wherein the first and the second serrated threads of the first and the second serration patterns form a part of a right-angled triangle. 
     
     
       4. The light guide plate of  claim 2 , wherein the first and the second serrated threads of the first and the second serration patterns form a part of an acute-angled triangle. 
     
     
       5. The light guide plate of  claim 2 , wherein each of the first and the second serrated threads of the first and the second serration patterns is composed of an oblique side and a curved side. 
     
     
       6. The light guide plate of  claim 2 , wherein each of the first and the second serrated threads of the first and the second serration patterns is composed of a first curved side and a second curved side having a radius of curvature smaller than that of the first curved side. 
     
     
       7. The light guide plate of  claim 1 , wherein the light input part further includes a third area, and the third area symmetrically emits the light around the normal line of the light input part. 
     
     
       8. The light guide plate of  claim 7 , wherein the third area includes a third serration pattern having a symmetrical cross section around the normal line of the light input part. 
     
     
       9. The light guide plate of  claim 8 , wherein a third serrated thread of the third serration pattern forms a part of an isosceles triangle. 
     
     
       10. The light guide plate of  claim 8 , wherein a pitch of the third serration pattern is formed to be smaller than a pitch of the first serration pattern or the second serration pattern. 
     
     
       11. The light guide plate of  claim 8 , wherein the third serration pattern includes curved sides symmetrically formed. 
     
     
       12. The light guide plate of  claim 1 , wherein the first area and the second area are arranged in parallel to a boundary part between the light input part and the light output part. 
     
     
       13. The light guide plate of  claim 1 , wherein either of the first area and the second area is protruded to form a stepped portion. 
     
     
       14. A display device comprising:
 a display panel on which an image is displayed; 
 a light source supplying light to the display panel; 
 a light input part including first and second areas to which light is incident; and 
 a light output part neighboring the light input part and outputting light; 
 wherein the light having passed through the first area is emitted with its light quantity distribution biased in a first direction, and the light having passed through the second area is emitted with its light quantity distribution biased in a second direction different from the first direction, and 
 wherein
 the first area includes a row of a first serration pattern each including a first serrated thread adjacent to a normal line of the light output part, 
 the second area includes a row of a second serration pattern each including a second serrated thread adjacent to the normal line, 
 the first serrated thread overlaps the second serrated thread, and 
 
 the second serrated thread is inclined from the normal line in a different direction than the first serrated thread. 
 
     
     
       15. The display device of  claim 14 , wherein the first and the second serration patterns are symmetrical to each other around the normal line of the light input part. 
     
     
       16. The display device of  claim 15 , wherein the first and the second serrated threads of the first and the second serration patterns form a part of a right-angled triangle. 
     
     
       17. The display device of  claim 15 , wherein the first and the second serrated threads of the first and the second serration patterns form a part of an acute-angled triangle. 
     
     
       18. The display device of  claim 14 , wherein the light input part further includes a third area, and the third area symmetrically emits the light around the normal line of the light input part. 
     
     
       19. The display device of  claim 18 , wherein the third area includes a third serration pattern having a symmetrical cross section around the normal line of the light input part. 
     
     
       20. The display device of  claim 14 , wherein the light source comprises a plurality of point light sources. 
     
     
       21. A method of improving uniformity of light emission from a light guide plate, the light guide plate including a light input part to which light is incident and a light output part neighboring the light input part and outputting light, the method comprising:
 forming a first area in the light input part to pass light therethrough with a light quantity distribution biased in a first direction, the first area including a row of a first serration pattern each including a first serrated thread adjacent to a normal line of the light output part; and, 
 forming a second area in the light input part to pass light therethrough with a light quantity distribution biased in a second direction, different than the first direction, the second area including a row of a second serration pattern each including a second serrated thread adjacent to the normal line, 
 wherein 
 the first serrated thread overlaps the second serrated thread, and 
 the second serrated thread is inclined from the normal line in a different direction than the first serrated thread.